Problem is for me to do what u did I can't because it would never fly by permitting even if I say I will use one or the other...I am told they will go by code and not by what process I will use. So I will be stuck with the 1 nema 14-50 permitted setup until I make lots of money to give to fpl to bring in proper service. It's frustrating...I thought I was going worry free from gas to electric and now I have to deal with this. Not sure what I will do with charging when I get the model x... I could just see the disaster with 1 nema plug and two cars...honey you forgot to plug in your car to charge...honey that is your job to make sure our cars are properly charged....
The code actually gives you a provision to do just what FarmerDave is saying, in that case. 220.60 says "where it is unlikely that two or more noncoincident loads will be in use simultaneously, it shall be permissible to use only the largest load(s) that will be used at one time for calculating the load..." It doesn't have a lock-out/interlock requirement - just "unlikely".
Now, with that said, it will be an inspector's determination. If you have an HPWC and a 14-50 for backup, you'll have an easier time convincing the inspector because the 14-50 is a backup, used in case of failure of the HPWC. But the inspector is less likely to accept it if there's a greater chance of the loads being drawn at the same time (e.g., you have cars plugged into both at the same time).
That particular clause has no black-and-white rule, so your inspector will be the one determining what you can do.
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I did what you are thinking of in anticipation of possibly getting a dual charger for my 70D. Seems dual drive would come with a dual charger yes? I didn't figure this out until I was deep into the process of getting my S. I keep the cord in my car and it's nice to have the wall mount with the Wall Connector. Plus if you let other dual charger S owners charge at your place, you can accomodate their needs. I'm planning to make mine available by listing myself on an app called PlugShare once I get my solar put on the house. I installed it toward front of garage for backing in or pulling in. About $1,200 by Tesla certified installer to install breaker box, install wall connecter, with permits et al.
Dual motor does not mean dual charger. On the Model S, the dual charger is an option that allows you to charge at up to 60 rated miles per hour/80A on a 240V/100A circuit with the HPWC, when compared to the standard, single-charger 30 rated miles per hour/40A on a 240V/50A circuit with the UMC or HPWC. It's an option that is installed only at the service center.
Model X does not have an option for dual chargers - there is only a single charger capable of charging at up to 48A (60A circuit), but Tesla offers a hidden option for a charger that will charge at up to 72A (90A circuit).
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around here, it is the power co.s responsibility to upgrade where necessary. The transformer on the pole that powers my house, & 4 others - I'm on the dead end - can either handle the load, or gets upgraded, free of charge. I then just pay $ for the extra use by kWh. The cost is built into everyone's bill, a "line charge". So I will pay Tesla for the hardware, the city for the permit, & the electrician for the work. Zero$ to the power Co. (?) as I understand it. :frown: Still a good chunk to add to a $128k bill, oh wait, they've had $5k for 3 years so it's "only" 123k :wink: about double the cumulative total of all the cars I have ever bought. & I'm pretty old!
Go Tesla!
The rules are different for every power company in every state and it's based on the regulations that states have adopted.
In my case (a member-owned co-op), the power company will supply you with the meter pan and will be responsible for all of the cost of installing and upgrading transformers & conductors up to that point, and the homeowner is responsible for the cost of installing the meter pan and upgrading the service conductors from the pan to the service panel(s), along with any other inside upgrades required. (Note: the power company will only do this if the demand calculation seems reasonable... I can't get 600A/800A/etc. service just because I ask for it - I need to submit the load calculations.)
Generally, the rules for investor-owned utilities are going to be tighter. They're going to try to pay the absolute minimum required by law for any upgrades. A good place to start is your public utilities commission - understand what the power companies are *required* to do first.
